/*
 * Copyright (c) 2017, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.oracle.svm.core.hub;

import org.graalvm.collections.EconomicMap;
import org.graalvm.nativeimage.ImageSingletons;
import org.graalvm.nativeimage.Platform;
import org.graalvm.nativeimage.Platforms;
import org.graalvm.nativeimage.hosted.Feature;

import com.oracle.svm.core.annotate.AutomaticFeature;
import com.oracle.svm.core.util.ImageHeapMap;

public final class ClassForNameSupport {

    static ClassForNameSupport singleton() {
        return ImageSingletons.lookup(ClassForNameSupport.class);
    }

    /** The map used to collect registered classes. */
    private final EconomicMap<String, Class<?>> knownClasses = ImageHeapMap.create();

    @Platforms(Platform.HOSTED_ONLY.class)
    public static void registerClass(Class<?> clazz) {
        if (PredefinedClassesSupport.isPredefined(clazz)) {
            return; // must be defined at runtime before it can be looked up
        }
        singleton().knownClasses.put(clazz.getName(), clazz);
    }

    public static Class<?> forNameOrNull(String className, ClassLoader classLoader) {
        Class<?> result = singleton().knownClasses.get(className);
        if (result == null) {
            result = PredefinedClassesSupport.getLoadedForNameOrNull(className, classLoader);
        }
        // Note: for non-predefined classes, we (currently) don't need to check the provided loader
        return result;
    }
}

@AutomaticFeature
final class ClassForNameFeature implements Feature {
    @Override
    public void afterRegistration(AfterRegistrationAccess access) {
        ImageSingletons.add(ClassForNameSupport.class, new ClassForNameSupport());
    }
}
